A printing apparatus to which a printing plate that is subject to plate-making is attached to printing means for performing a printing operation generally includes a stencil discharging box for receiving used printing plates (used stencils). In the printing apparatus described above, the used stencil that is unnecessary after the completion of the printing operation is removed from the printing means and stored in the stencil discharging box as compressed. The stencil discharging box is generally detachable to the printing apparatus in order to discharge the used stencil. Patent Documents 1 and 2 described below illustrate the conventional stencil discharging box described above.
Patent Document 1 (Japanese Unexamined Patent Application No. 2002-96542) discloses a stencil discharging box having an integral simplified structure in which a single plate member having elasticity is folded so as to have generally a U-shaped section. This stencil discharging box is detachably mounted to the printing apparatus by utilizing its elasticity, wherein the gap at the front end is suitably opened to receive a used stencil when it is mounted. In order to detach the box from the printing apparatus, the gap at the front end is closed by the hand-gripping force, so that the used stencil is prevented from being dropped to the outside. When a user loosens his/her grip after he/she carries the box to a discarding position, the used stencil inside can be discarded from the opened gap at the front end.
Patent Document 2 (Japanese Unexamined Patent Application No. Hei 11-198512) discloses a stencil discharging box that is detachably mounted to a printing apparatus and has a box-like main body. A used stencil sent toward the inside of the stencil discharging box is compressed by a compressing plate that moves along an inner circumference plane. When the used stencil is discarded, a user pulls a handle, provided to the main body, with one hand to draw the box in the near side of the printing apparatus so as to remove the box, and then, operates another handle with the other hand to move a pushing member at the inside of the main body, whereby the used stencil is pushed and discarded to the outside from the main body in the direction orthogonal to the stencil receiving direction.
The stencil discharging box disclosed in Patent Document 1 is detachably mounted to the printing apparatus with one hand as described above. Further, when a user loosens his/her grip to the stencil discharging box and opens the front opening, the used stencil can be discharged and discarded from the inlet (the manner in which the used stencil is discarded in the direction reverse to the receiving direction of the used stencil is referred to as “lateral discard”). However, when the used stencil bites between ribs, which are formed at the surface in the box for preventing the used stencil from sticking, due to the compression of the used stencil, the used stencil inside might not be discharged just by tilting the box with the front opening opened. Thus, the problem might occur in the reliability of discarding work.
The stencil discharging box has a simple structure in which a single plate is folded into a U-shape, and according to the balance between the elasticity and the grip of the user, this box is attached to or detached from the printing apparatus or prevents the used stencil from being dropped upon the detachment. Therefore, the box might not appropriately be attached to or detached from the printing apparatus, or the used stencil might be dropped upon the detachment, depending upon the discretion of the user.
Since the stencil discharging box is formed from a single plate that is folded into a U-shape, both side faces are open, and it can be considered that the used stencil is discharged and discarded from the openings (the manner in which the used stencil is discarded from the opening, having a narrow width, at the side face in the direction different from the receiving direction of the used stencil is referred to as “vertical discard”). However, when the used stencil is compressed and bites between the ribs that are formed at the surface in the box for preventing the used stencil from sticking, a greater resistance is applied to the case of the vertical discard than the lateral discard, in which the used stencil is discarded in the direction orthogonal to the longitudinal direction in which the ribs extend, so that the vertical discard cannot actually be executed.
According to the stencil discharging box described in Patent Document 2, when the used stencil is discarded, a user pulls a handle, provided to the main body, with one hand to draw the box in the near side of the printing apparatus so as to remove the box, and then, operates another handle with the other hand to push and discard the used stencil to the outside from the main body. As described above, both hands has to be used in the stencil discharging box in order to discard the used stencil to the outside of the box, which makes the work complicated.